The scientific data appear to make clear that global warming is, in fact, happening. We know that 2012 was the hottest year on record in the continental United States. We also know that every year for the past 36 years has been warmer than the long-term average. This seems to indicate that the world is warming up.

We know that the melting of the polar ice caps would make a huge difference to our world because it would flood many coastal areas and low islands. Sea levels are rising to some degree already, but this has yet to have a major impact on human beings. It is also true that there are some aspects of the natural environment that are changing. We know that precipitation has increased and that some plants and animals are moving because the places where temperatures are congenial for them have moved.

There has been speculation about the current impacts of global warming on the weather. We have had some very severe hurricanes in past years. We have also had more severe weather of all sorts (heat waves, droughts, heavy snow) recently.

Global warming may cause sea levels to rise and it may make some areas that are currently good for agriculture much less conducive to growing crops.